1. Field of the Invention
The invention relates to a method for the manufacture of a no-contact or contact-free card (namely a card that operates without making contact) as well as to a contact-free card comprising a card body, an electronic module and, connected to said module, an antenna. Such cards are designed to carry out various operations such as, for example, debiting operations in public transport vehicles, notably in subway systems, banking operations, telephone communications or various identification operations. These operations are performed by means of a remote electromagnetic coupling between the electronic module of the card and a receiver apparatus or reader. The coupling can be done in read mode or in read/write mode.
In the form in which they are made at present, cards are portable objects with standardized dimensions. However, in the case of contact-free cards, the thickness of these portable objects is often greater. The usual ISO 7810 standard corresponds to a card with a standard format having a length of 85 mm, a width of 54 mm and a thickness of 0.76 mm. Each contact-free card has a card body constituted by an assembly of thermoplastic sheets and an electronic module containing an integrated circuit chip. An inductance coil type of antenna is connected to the chip.
2. Description of the Prior Art
There are known ways of making contact-free cards by the colamination technique. These methods entail the placing, between the two plates of a press, of a stack of thermoplastic sheets in the middle of which the contact-free electronic module is positioned, this contact-free electronic module being already connected to an antenna surrounding the module. The different thermoplastic sheets are then soldered by the application of pressure and temperature.
Owing to the differences between the expansion coefficients of the materials used, the combined action of the pressure and of the temperature generates a residual deformation on the surface of the card and below the electronic module. Zones of differential resistance to impacts and to twisting forces are created. The card obtained is not aesthetically satisfactory, unless the thickness is increased, which means that it is often not possible to obtain the above-mentioned standard thickness of 0.76 mm. The efficiency of such methods is therefore low. Furthermore, since the rejected cards already contain the electronic module and the coil, these methods are particularly costly.
Furthermore, there already exist methods for the making of contact-free cards in which a rectangular frame is deposited on a lower thermoplastic sheet. An electronic module, already connected to an antenna, is deposited within a cavity formed by said frame and said internal sheet, and a thermosetting resin is poured into this cavity, and then this cavity is covered with an upper thermoplastic sheet.
Cards made by such methods have an unaesthetic sinusoidal strip on the edge. Furthermore, the positioning of the module inside the card is done in just a very approximate fashion. It is therefore very difficult to add a contact interface to cards made by such methods.
The present invention is aimed at proposing a method for the manufacture of contact-free cards that overcomes the above-mentioned drawbacks and makes it possible, in particular, to easily obtain aesthetically pleasing, slim cards efficiently and at low cost, minimizing the lack of precision of the mounting of the the electronic module in the card body.
Another aim of the invention is the addition of a contact interface to contact-free cards in order to obtain a combined or hybrid card having two modalities of operation: contact-free operation and operation with contacts.